Monitoring systems for the railroad industry provide methods and apparatus for automatic determination of the temperatures of components including wheels and wheel bearings on passing trains, infrared (IR) radiation radiating from the wheel or wheel bearing of a train traveling along a train track is indicative of a temperature or temperature range of the wheel or wheel bearing. IR scanners and associated circuits for detecting an overheated wheel or wheel bearing are available commercially. Some systems utilize an IR detector located in close proximity to the railroad tracks. The IR detector determines the presence of radiated IR waves within a predefined range of wavelengths. The IR detector also produces an output signal indicative of the power or intensity of the sensed IR radiation within the predefined range.
One problem associated with these types of systems for detecting a temperature range or a temperature of a railroad train wheel or wheel hearing involves inaccuracies that may result under different conditions. In situations where the range of detected IR waves is attenuated or filtered by external sources such as blowing snow, wind, rain, or other weather conditions, the result is an inaccurate detection of a hot wheel or hot bearing condition. Accurate detection of an overheated component such as a wheel or wheel bearing allows for corrective actions to be taken before the overheated component breaks down or fails.
One attempt to avoid the problem of inaccurate detection of wheel and bearing temperatures in a harsh environment is disclosed in U.S. Pat. No. 6,872,945 to M. Bartonek that issued on Mar. 29, 2005 (the '945 patent). The '945 patent discloses an apparatus that includes a sensor for sensing IR radiation radiating from a train wheel or bearing within two or more IR wavelength ranges, where each wavelength range does not substantially overlap with any other wavelength range. The sensor generates signals indicative of the sensed IR radiation in each of the wavelength ranges. A processor determines a temperature range or a temperature of the wheel or wheel bearing from the generated signals.
The temperature detection system of the '945 patent may determine a temperature of a wheel or wheel bearing of a train traversing a railroad track. Furthermore, the temperature detection system of the '945 patent may not be susceptible to variations in the amplitude, intensity, or power of the detected IR radiation. However, this solution may still provide a less than optimal temperature detection system. The temperature detection system of the '945 patent may still be susceptible to certain disadvantages associated with the particular type of temperature detecting technology that is being used. For example, the temperature detection system of the '945 patent may use an array of the same type of detectors, each of which may detect a limited bandwidth range, but each of which may still be susceptible to the same disadvantages associated with the type of technology being used, such as slow response time, or susceptibility to errors caused by microphonics.
The system and method of the present disclosure solves one or more problems set forth above and/or other problems in the art.